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In this study, the effect on the degree of organoclay exfoliation in polypropylene‐ethylene (PP‐EP)/Ethylene vinyl acetate (EVA)/organoclay blend system was studied while varying organoclay structural characteristics. Cloisite 6A, Cloisite 15A, Cloisite 20A, Cloisite 25A, Cloisite 30B, Cloisite 93A, and Cloisite 10A were used because they have different type of modifier. Ternary PP‐EP/EVA/organoclay system was obtained with each type of clay and results were organized to analyze the effect of type of clay chemical modification (C20A, C15A, and C6A), steric effect caused by surfactant structure (C15A and C10A), length of substitute groups on the surfactant (C20 and C25A), and surfactant polarity (C30B and C93A). Samples were characterized by: wide angle X‐ray diffraction, scanning transmission electron microscopy (STEM), dynamic mechanical analysis, and capillary rheometry. Results showed that clay galleries can be saturated with chemical modifier complicating the polymer chain intercalation into the clay galleries. Some clay modifier substituent groups could cause certain steric effect promoting less exfoliated platelets structures. Finally, longer chains in the modifier substituent group can promote a better intercalated–exfoliated structure. Among all the studied organoclays, best results were obtained in the ternary system when using C20A, which modifier has two hydrogenated tallows. In this case, interlayer spacing was increased more noticeable after ternary system was formed. This was corroborated with the obtained increase in viscosity and the intercalated–exfoliated structure observed by STEM. POLYM. COMPOS., 35:2241–2250, 2014. © 2014 Society of Plastics Engineers

A metallurgical by product mostly constituted of Wustita (FeO) was transformed to Magnetite (Fe3O4) spheres using a flame treatment. Then magnetite spheres surface was modified by cold plasma treatment with ethylene, where a thin polyethylene film was deposited on the spheres surface. Finally, HDPE composites with modified spheres were obtained by melt mixing and its thermal conductivity was determined by MDSC. It was found that spheres surface modification helps to increase composites thermal conductivity.